Suturing needles used for suturing the biological tissues are broadly divided into a form of piercing the tissues to be sutured and extending by force and passing through the tissues and a form of cutting and passing through the pierced tissues as a base point. The suturing needle optimum for the tissues to be sutured is selected for use.
The suturing needle having the former form is formed as a circular needle having a circular section in its entirety from a needle tip portion for piercing the tissues through a trunk portion to a distal end. A needle tip as the tip of the needle tip portion is formed to have a sharp point or a blunt spherical shape. The suturing needle having the latter form is formed as an angular needle having a section from a needle tip to a trunk portion, which has a polygonal shape represented by a triangular shape. A needle tip is formed to have a sharp point or a blunt shape concentrated by plural faces configuring the polygonal shape. Cutting edges are formed on two or more ridge lines configuring the angular shape.
To realize easy suturing by reducing the labor of an operator, the circular needle and the angular needle have been improved in view of how much the resistance (piercing resistance) is reduced when piercing and passing through the biological tissues. However, even if the piercing resistance is reduced, the entire resistance cannot be eliminated.
Being too sharp in order to reduce the piercing resistance, the tip easily pierces the glove or skin of the operator to damage his/her skin. Infection due to the blood or body fluid of a patient can occur.
In order not to easily tear the glove on contact with the tip, the circular needle having the blunt tip has been proposed (see U.S. Pat. No. 5,693,072). In this technique, a needle tip portion (a tip portion 12) is formed to have a circular section and a spherical tip. To exhibit good stability and operability in use, a trunk portion (a shaft portion 11) has an hourglass-like or rectangular section having two flat faces.
For the angular needle, there has been proposed the suturing needle which has the blunt tip by grinding one face configuring a polygonal shape (see Japanese Patent Application Laid-Open (JP-A) No. 6-296790). In this technique, even if the blunt needle tip is brought into contact with the operator, the risk of hurting him/her is reduced. The risk of infection due to the blood or body fluid of the patient can be reduced.
The suturing needle is held by a needle holder for operation. The curved suturing needle held by the needle holder can be rotated by the acting force in the operation by the needle holder. Thus, there has been proposed a technique in which at least one plane region is formed in the longitudinal direction of the suturing needle and at least one rib or, if possible, two ribs in the longitudinal direction are formed in the plane region so as to engage the sawtooth portions of the needle holder, thereby preventing the rotation of the suturing needle (see Japanese Patent Application Publication (JP-B) No. 43-15511).